I don't think they would give Sloan $3M in any scenario. I don't think they had him valued that highly. They would likely give that money to a guy like Kash Mayfield but not Sloan.
You also have to remember the key is to hit on that first pick. Pittsburgh already fucked up this scenario when they underslotted Henry Davis at 1-1 and he's awful. They totally biffed 1-1. He's so bad he can't play ahead of Joey Bart or Yasmani Grandal. With the first pick I'll take the high floor/high ceiling college lefty over a low floor/high ceiling HS position player with a questionable hit tool.